In call centers with centralized trunking, recording may be centralized at the ingress or egress point of the call center trunks rather than at the edge network where the phones are physically located. Recording centrally reduces the number of interception points greatly simplifying the network topology requirements for recording. To obtain the maximum business value from call center recording, the recording system should capture the context of the call including the agent taking the call and other auxiliary business information surrounding the call. This context information is typically available through a Computer Telephony Integration (CTI) event integration to the call center PBX.
The challenge is to correlate the auxiliary business information with a media stream being recorded. In non-gateway recording environments correlating the auxiliary information is available in the primary communication channel (e.g., the call SIP signaling carries the call center agent's extension number or IP address of RTP stream end point). However, in gateway recording environments, it is possible that the primary communication channel does not provide correlating information. Yet further, in some environments, the primary communication channel provides correlating information for some calls but not others depending on the flow of the call in the environment. For example the media for some calls may flow directly to the agent's phone for some calls but be routed back to the PBX or conference resource for other call flows. When the call is diverted away from the phones, the information in the primary information channel may no longer be available for correlation to auxiliary business information.